Golf club with fixed-tension shaft

Abstract

A golf club having a hollow shaft whose flexibility is determined by the tension on a wire coinciding with the shaft longitudinal axis. The is attached between a fixed assembly in the handle and a fixed assembly at the shaft lower end. The upper assembly includes a cap member, a wire-end clamping member, and a tension support member. A first embodiment uses a thin round wire. A second embodiment uses a thin tape-shaped wire.

What is claimed is:  
     
       1. A golf club comprising: 
       a handle with a cavity having an upper portion and a lower portion;  
       a hollow shaft upper portion terminating in an upper end closely received within the cavity lower portion and symmetric about a longitudinal axis;  
       a hollow flexible shaft portion, symmetric about said axis, attached at an upper end to the shaft upper portion and attached at a lower end to a hollow shaft lower portion symmetric about said axis, the shaft lower portion terminating in a lower end;  
       a cap member having an inner thread and an outer surface, said outer surface closely received within the handle cavity upper portion;  
       a wire-end clamping member having therethrough a longitudinal bore of a predetermined cross-section, the clamping member having opposed generally planar upper and lower ends, the clamping member radially compressible, the cap member superposed upon the compressed clamping member;  
       a tension support member having a generally cylindrical lower portion closely received within the shaft upper portion, a generally cylindrical upper portion having an outer thread, and an annular flange having opposed generally planar upper and lower surfaces, the flange disposed between and attached to said upper and lower portions, the flange lower surface contacting the upper end of the shaft upper portion, the cap member inner thread in threaded combination with the outer thread of said upper portion; and  
       a metallic wire having opposed upper and lower wire-ends and disposed along said axis, the upper wire-end maintained within said clamping member, the lower wire-end attached to the lower end of the shaft lower portion, the wire maintained at a preselected constant tension.  
     
     
       2. A golf club comprising: 
       a handle having a cap portion attached to a grip portion having a generally cylindrical interior surface and a scallop-contoured, symmetrically downwardly tapering exterior surface, the cap portion and interior surface determining a generally cylindrical cavity having an upper portion and a lower portion;  
       a hollow inflexible, downwardly tapering shaft upper portion terminating in an upper end closely received within the cavity lower portion and symmetric about a longitudinal axis;  
       a hollow flexible, downwardly tapering shaft central portion, symmetric about said axis, attached at an upper end to the shaft upper portion and attached at a lower end to a hollow inflexible shaft lower portion symmetric about said axis, the shaft lower portion having an inner wall and terminating in a lower end;  
       an upper wire-end retainer assembly comprising a cap member having a top portion, a generally cylindrical outer surface, and an inner thread, said outer surface closely received within the handle cavity upper portion, said assembly further comprising a hexagonal-shaped wire-end clamping member having opposed generally planar upper and lower ends, an outer surface, and a longitudinal bore therethrough of a constant predetermined cross-section, the clamping member radially compressible, the cap member superposed upon the compressed clamping member, said assembly further comprising a tension support member having a generally cylindrical lower portion closely received within the shaft upper portion, a generally cylindrical upper portion having an outer thread, and an annular flange having opposed generally planar upper and lower surfaces, the flange disposed between and attached to said upper and lower portions, the flange lower surface contacting the upper end of the shaft upper portion, the cap member inner thread in threaded combination with the outer thread of said upper portion;  
       a lower wire-end retainer assembly comprising a generally cylindrical sleeve extending in a generally cylindrical flange, the sleeve and flange having therethrough a common bore, a ring received within the flange, the flange rigidly attached to said inner wall of the shaft lower portion at said lower end; and  
       a metallic wire of a constant predetermined cross-section having opposed upper and lower wire-ends and disposed along said axis, the upper wire-end closely received within the bore of the wire-end clamping member, said wire-end secured within the clamping member after the clamping member is radially compressed, the lower wire-end attached to said ring of the lower wire-end retainer, the wire having a constant preselected tension.  
     
     
       3. The golf club of  claim 2 , further comprising a plurality of support members each having a bore therethrough, the bores aligned with said longitudinal axis, the wire passing through each bore. 
     
     
       4. The golf club of  claim 3 , wherein the support members are fabricated from a material having a low friction coefficient. 
     
     
       5. The golf club of  claim 4 , wherein the wire is made from a material selected from the group consisting of stainless steel, titanium, and spring-wire having a Rockwell hardness in a range of 30 to 70, and has a circular cross-section with a diameter in a range from 0.032- to 0.090-inch. 
     
     
       6. The golf club of  claim 4 , wherein the wire is made from a carbon steel having a Rockwell hardness in a range of 30 to 75, and has a circular cross-section with a diameter in a range from 0.025- to 0.090-inch. 
     
     
       7. The golf club of  claim 4 , wherein the wire is made from tungsten having a Rockwell hardness in a range of 75 to 80, and has a circular cross-section with a diameter in a range from 0.031- to 0.055-inch. 
     
     
       8. The golf club of  claim 4 , wherein the wire is made from a material selected from the group consisting of stainless steel, carbon steel, titanium, and spring-wire having a Rockwell hardness in a range of 30 to 70, and has a rectangular cross-section having a width in a range from about 0.032- to about 0.125-inch and a thickness in a range from about 0.005- to about 0.025-inch. 
     
     
       9. The golf club of  claim 4 , wherein the wire is made from tungsten having a Rockwell hardness in a range of 40 to 80, and has a rectangular cross-section having a width in a range from about 0.032- to about 0.125-inch and a thickness in a range from about 0.005- to about 0.025-inch. 
     
     
       10. The golf club of  claim 4 , wherein the preselected wire tension is in a range from about 30 pounds-weight to about. 400 pounds-weight.